synthesis, characterization and photothermal therapy performance of cu-doped nir-cqds

Abstract: carbon quantum dots (cqds) are a new class of carbon nanomaterials that have emerged recently and have garnered much interest as potential competitors to conventional semiconductor quantum dots [1]. the accidental discovery of cqds during the separation and purification of single-walled carbon nanotubes (swcnts) by xu et al. in 2004 triggered subsequent studies to exploit the fluorescence properties of cqds and create a new class of viable fluorescent nanomaterials [2]. in addition to their comparable optical properties, cqds have the desired advantages of low toxicity, environmental friendliness low cost and simple synthesis process [1] and potential photoacoustic, photothermal and photodynamic functions. based on these eye-catching properties, cqds are considered to be favorable candidates for construction of multifunctional cancer photo theranostic platforms. in order to exploit cqds in photothermal therapy applications, tuning their absorption in nir regions are necessary for both deep tissue fluorescence imaging and phototherapeutic functions [3]. the cu-cqds was prepared by hydrothermal method using cucl2 and citric acid in this work, photothermal properties of cqds were studied and applied for in-vitro cancer cell therapy. an aqueous suspension of 3 ml of 7.5 × 10-4 m cu-cqds showed a rapid temperature increase of more than 59 °c after 10 minutes’ irradiation with an 808-nm laser. the photothermal effect was studied on mcf-7 cell and acceptable results were obtained. for there we can use it for targeted and effective cancer therapy without side effects.